LoginController.java

package security;

import org.springframework.security.core.Authentication;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

@RestController
@RequestMapping("/api/login")
public class LoginController {

    @RequestMapping
    public LoginStatus status(Authentication principal) {

        return principal == null ? new LoginStatus(false, null) : new LoginStatus(true, principal.getName());
    }
}